Game of Thrones casts Ian McShane in season 6 mystery role 

news: Ian McShane is coming to Westeros! The Emmy-winning British actor is joining

season 6, EW has learned exclusively. The move returns the former

The show’s tight-lipped production will not reveal any details about McShane’s character, who’s coming on board for the most mysterious season yet.

is preparing to dive headlong into narrative territory not yet revealed in author George R.R. Martin’s novels (and despite that opening sentence, McShane’s character could theoretically appear in Westeros or Essos or somewhere in between).

We can tell you, however, that sources say McShane has a relatively small amount of screen-time during the season, yet his character is of key importance.

McShane launched to American TV stardom by playing a mesmerizingly homicidal frontier kingpin Al Swearengen on

and many others. His most recent regular TV gig was an arc on Showtime’s 

has a reputation for making stars of its enormous ensemble cast more than casting already widely known performers, McShane is easily one of the most recognizable actors to ever sign on with the series. Plus, fans of his work—especially on the artfully written 

has started production on season 6 and is expected to return for 10 episodes next spring. Earlier this week, HBO’s programming president Michael Lombardo revealed that the network plans at least eight seasons of the show, a bump from the oft-reported seven season plan.

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